Side-shifting mill roll

ABSTRACT

Mill roll changing apparatus for positioning transversely of a rolling mill pass line and arranged for receiving and inserting mill rolls relative to a juxtaposed mill stand comprises a movable floor section normally covering a roll changing pit adjacent the mill stand, a support structure for the floor section and positionable within the pit, and a number of rails on the floor section. Driving mechanism is provided for moving the floor section laterally of the support structure in a direction generally parallel to the mill pass line so that selected pairs of the floor section rails can be laterally aligned with a pair of rails within the mill stand. An elevating mechanism mountable within the pit is structured for elevating the floor section to a first position above an existing floor surrounding the pit so that the floor section can be moved laterally thereof and to a second position whereat the floor section is flush with the existing floor and to a third position whereat the floor section is recessed within the roll-changing pit.

Petros States Patent 91 Oct. 22, 1974 SIDE-SHIFTING MILL ROLL Andrew J.Petros, Oakdale, Pa.

[73] Assignee: Mesta Machine Company,

Pittsburgh, Pa.

[22] Filed: June 20, 1973 [211 Appl. No.: 371,766

[75] Inventor:

Primary Examiner-Milton S. Mehr Attorney, Agent, or Firm-D0nn J. Smith 57 ABSTRACT Mill roll changing apparatus for positioning transversely ofa rolling mill pass line and arranged for receiving and inserting millrolls relative to a juxtaposed mill stand comprises a movable floorsection normally covering a roll changing pit adjacent the mill stand, asupport structure for the floor section and positionable within the pit,and a number of rails on the floor section. Driving mechanism isprovided for moving the floor section laterally of the support structurein a di rection generally parallel to the mill pass line so thatselected pairs of the floor section rails can be laterally aligned witha pair of rails within the mill stand. An elevating mechanism mountablewithin the pit is structured for elevating the floor section to a firstposition above an existing floor surrounding the pit so that the floorsection can be moved laterally thereof and to a second position whereatthe floor section is flush with the existing floor and to a thirdposition whereat the floor section is recessed within the roll-changingpit.

10 Claims, 5 Drawing Figures SlDE-SHIFTING MILL ROLL The presentinvention is an improvement upon certain aspects of the roll changingarrangement described and claimed in coassigned U.S. Pat. No. 3,451,244granted to W. L. Stover et al. The invention is also an improvement overcertain roll changing systems illustrated in Mesta Machine Companybrochure entitled Mesta Work Roll Changing Systems, copyright 1966.

The present invention relates to a side-shifting mill roll changingsystem or apparatus, and more particularly to a system of thecharacter'described having novel means for effecting the side-shiftingof one of both assemblies of withdrawn and replacement mill rolls.

The system of my present invention enables mill rolls to be changedquickly and efficiently utilizing components of simplified mechanicalconstruction. Although the mill roll changing system is describedprimarily in connection with the work and back-up rolls of a four highmill stand, it will be evident that the principles of the invention areapplicable to other types of rolling mills and other types of rollassemblies. It will also be readily apparent as this descriptionproceeds that the present .roll changing system can be used inconjunction with either hot or cold rolling mills.

Numerous systems have been proposed heretofore for changing mill rollsin various types of rolling mills. For the most part these prior systemshave been limited in applicability, have consumed valuable manufacturingspace, in many cases have created personnel hazards, and have beenunduly and mechanically complicated both from a first procurment pointof view as well as for continuing maintenance. Frequently, there areunnecessary losses in production and personnel time during theroll-changing operation.

The conceptualization of the present invention extends considerably theapplicability of mechanized roll changing operations to a wide range .ofroll sizes and floor line to pass line dimensions. The'roll-changingprocedures involved in my present invention are simplified in comparisonwith previous systems and require fewer mechanical components.Unnecessary complexities in the roll changing apparatus are therebyavoided, and operation and maintenance are considerably improved. Theside-shifting technique, upon which my novel roll changing system isbased, clears the mill area floor of usual roll changing components andprovides a flush floor structure when the roll changing system is notactively in use. In consequence, the overall production time of a givenrolling mill is enhanced, and many personnel hazards, such as tripping,are eliminated.

I overcome the disadvantages of the prior art and accomplish theaforementioned desirable results and improvements by providing mill rollchanging apparatus for positioning transversely of a rolling mill passline and-arranged for receiving and inserting mill rolls relative to ajuxtaposed mill stand, said apparatus comprising a movable floor sectionnormally covering a roll changing pit adjacent said mill stand, asupport structure for said floor section and positionable within saidpit, a number of rails on said floor section, driving mechanism formoving said floor section laterally of said support structure in adirection generally parallel to said pass line so that selected pairs ofsaid rails can be laterally aligned with a pair of rails within saidmill stand, and an elevating mechanism mountable within 2 said pit andstructured for elevating said floor section to a first position above anexisting floor surrounding said pit so that said floor section can bemoved laterally thereof and to a second position whereat said floorsection is flush with said existing floor'and to a third positionwhereat said floor section is recessed within said pit.

I also desirably provide a similar roll-changing apparatus wherein saidpit is elongated in a direction transversely of said mill pass line andextends beneath said existing floor, and guideways are mounted in saidpit and beneath said existing floor, said guideways being aligned withthe lowermost position of said floor section, and traction means areprovided for drawing said floor section and its support along saidguideways to a position beneath said existing floor and away from theopen area of said pit.

I also desirably provide a similar roll-changing apparatus wherein saidpit is shaped to receive a lower backup roll assembly from said millstand and said traction means are coupled to said lower assembly fordrawing said assembly into said pit simultaneously with withdrawal ofsaid floor section and said support to their position beneath saidexisting floor.

I am aware of a number of previous efforts in this field typified forexample by the patents to Simmonds U.S. Pat. No. 3,611,779; Sevenich etal. U.S. Pat. No. 3,695,080; and Eibe U.S. Pat. No. 3,698,226. Thesepatents, however, do not disclose the novel features of the invention asset forth above.

During the foregoing discussion, various objects, features andadvantages of the invention have been set forth. These and otherobjects, features and advantages of the invention together withstructural details thereof will be elaborated upon during theforthcoming description of certain presently preferred embodiments ofthe invention and presently preferred methods of practicing the same.

In the accompanying drawings I have shown certain presently preferredembodiments of the invention and have illustrated certain presentlypreferred methods of practicing the same, wherein:

FIG. 1 is a side elevational view, partially in vertical section, of oneform of roll changing system according to the invention; 1

FIG. 2 is a top plan view of the apparatus shown in FIG. 1;

FIG. 3 is a vertically sectioned view of the apparatus as shown in FIG.1 but taken along reference lines III- -III thereof;

FIG. 4 is apartial view similar to FIG. 1 but showing the system in araised operating position; and

FIG. 5 is a view similar to FIG. 1 but showing components of thechanging system in a lowered and withdrawn position for back-up rollchanging. 7

With reference now initially to FIGS. l3 of the drawings, in greaterdetail, an exemplary form of my novel mill roll changing system 20 isillustrated therein in connection with a mill stand shown partially at22 and a replacement work roll assembly 24. The mill stand 22 typicallycan be a four-high stand, of which the upper backup roll has beenomitted for purposes of illustration. The work roll assembly 24'includes a pair ofwork rolls 26, 28 each of which is provided with apair of bearing chocks 30 or 32. The bearing chocks 32 of the lower workroll 28 desirably are provided with railway trucks 34, 36 respectivelyfor engagement with pairs of rails 38, 40 (FIG. 2) on side-shiftingfloor plate 42. Depending upon the particular chain-outlined position 44or 46 (FIG. 2) of the side-shifting plate 42, one pair or the other ofthe rails 38, 40 is aligned with upper internal rails 48 of the millstand 22, and with additional rails (not shown) leading from theside-shifting floor plate 42 to the roll shop.

The mill stand 22 additionally is provided with a lower pair of rails 50located beneath the work roll rails 48 for reception of the lowerback-up roll 52, the bearing chocks 54 of which are likewise providedwith railway trucks 56. The work roll assembly 24' located within themill stand 22 is of course similarly constructed relative to thereplacement work roll assembly 24 described briefly above.

The side-shifting floor plate 42 is mounted upon support plate 58 bymeans of a number of slides or tychoway type bearings or the likedenoted generally by the reference character 60. The movable floor plate42 is shifted between its limit positions denoted by the aforementionedchain-outlines 44, 46 in FIG. 2 by suitable drive mechanism denoted byreference numeral 62 and slung from the underside of the support blade58 as better shown in FIGS. 1 and 3. The drive mechanism 62,

in this example including electric motor 64 and reducer 66, are thusmounted for movement with the support plate 58.

Linear motion is transmitted to the floor plate 42 in effecting theaforementioned movements thereof by means of output pinion 68 of thereducer 66, a pair of idler pinions 70, 72 mounted on common shaft 74for rotation therewith, and a pair of gear racks 76, 78 affixed to theunderside of the floor plate 42 and enmeshed respectively with the idlerpinions 70, 72. The common shaft 74, as part of the drive mechanism 62,likewise is mounted on the underside of the support plate 58 formovement therewith, for example, by a pair of pillow blocks 80. Toprevent exessive loadings upon the bearings 60 and the gear racks 76, 78particularly in the lateral directions thereof, i.e., longitudinally ofthe work roll assembly 24, a pair of slides and slideways denotedgenerally by the referenced numeral 82 are formed cooperatively on thefloor plate 42 and the support plate 58 to absorb inertial loadingsowing to starting and stopping of the roll assembly 24 or 24' wheneverpositioned on the side-shifting floor plate 42.

The floor plate 42 and its supporting plate 58 are movable in thisexample to three elevational positions represented in FIG. 1 by thesolid outlines of the plates 42, 58 and by chain-outlines 84, 86thereof. The uppermost or operating position 84 is seen more clearly inFIG. 4.

At the floor level elevation of the side-shifting plate 42 and itssupport plate 58, as denoted by the solid outlines thereof in FIGS. 1and 3, the floor plate 42 is flush with the surrounding floor areas ofthe mill, which areas are denoted by reference numeral 88 (FIG. 3). Atthis inactive position of the roll changing components the floor plate42 virtually eliminates any tripping hazard and any obstruction ofnormal mill activities in or about the roll changing area. Infurtherance of this purpose, as evident from FIG. 3, the pairs of rails38, 40 desirably are machined into the upper surface of theside-shifting floor plate 42.

As evident from both FIGS. 1 and 3 at the solid outline or floorelevation of the plates 42, 58 the rails 38,

40 of the side-shifting plate 42 are depressed below the elevation ofthe upper or work roll mill rails 48. In order to secure alignment ofthe plate rails 38, 40 with the upper mill rails 48, and to permitlateral shifting of the floor plate 42, the floor plate and itssupporting plate 58 are raised to its uppermost elevation 84 (chainoutline in FIG. 1, solid in FIG. 4). At this elevation the floor plate42 can be shifted between its positions 46, 44 (FIG. 2) in order toalign first its rails 38 with the upper mill rails 48 for withdrawal ofthe used work roll assembly 24' onto the rails 38. The drive mechanism62 is then energized in the opposite direction to align the plate rails40 at position 44 with the mill stand upper rails 48 so that theplacement assembly 24 can be inserted into the mill stand 22.

At the lowermost elevation 86 of the side-shifting floor plate 42 andits supporting plate 58, slide blocks 90 (FIG. 3) are lowered to theirchain outline position 92 to rest on slideways 94 of the below floorlevel foundation structure. At this elevation the entire roll changingsystem 20 can be withdrawn rearwardly on the slideways 94 as the lowerbackup roll assembly 52-54 is withdrawn from the mill stand 22 along themill stand lower rail sections 50 and along a pair of rails 96 alignedtherewith in the roll-changing pit 97.

The side-shifting floor plate 42 and its support plate 58 are elevatedto the three positions described above by convenient and unexpectedelevating means mounted generally beneath the floor opening 98 andwithin the roll-changing pit 97 (FIGS. 1, 3, and 4). The elevating meansare arranged to permit sliding of the support plate 58 thereover, whenthe support plate 58 and the floor plate 42 thereontogether with thelower backup roll 52 and withdrawn from the mill as shown in FIG. 5.Provision is also unexpectedly made by the present invention forwithdrawing both the floor plate 42 and the support plate 58 by the sametraction mechanism used in withdrawing and replacing the lower backuproll 52.

In furtherance of this purpose drawbar 100 for the lower backup roll 52is provided with a pedestal 102 rigidly mounted thereon as best shown inFIGS. 1 and 4. The pedestal 102 is slidably inserted into a generallytubular driving connection 104 secured to the underside of the supportplate 58 adjacent the forward end thereof. The sliding connectionbetween the components 102, 104 allows elevation of the side-shiftingfloor plate 42 and its support 58 without decoupling from the tractionmechanism for the lower backup roll bearing chock 54, including thedrawbar 100. Suitable traction means, such as a long stroke piston andcylinder arrangement 106 are coupled to the drawbar 100 for withdrawingand replacing the lower backup roll assembly 52-54 and for simultaneousmovements of the side-shifting plate 42 and its support 58 along theslideways 94.

One form of the aforementioned elevating means for the side-shiftingfloor plate 42 includes a pair of cylinder arrangements 108, 110 (FIGS.1 and 3) which are pivotally mounted on, and suspended between,respective pairs of abutments 112, 114. A pair of the cylinderarrangements 108, 110 and associated components are utilized such thatthe driving mechanism 62 for the laterally shifting floor plate 42 canpass therebetween as evident from FIG. 3.

Each of the cylinder arrangements 108, 110 in this example includesfirst and second cylinders 116, 118 of which the cylinder 116 is ofrelatively longer stroke and the cylinder 118 is of relatively shorterstroke. In other spatial arrangements of the invention it is conceivablethat the strokes of the pistons 116, 118 can be the same or that thestroke ralationship can be reversed. in the illustrated example, thedistal end 120 of each pistoncylinder arrangement 116 is pivoted to theassociated forward abutment 112 while distal ends 122 of the shorterstroke piston-cylinders 118, are pivoted respectively to cranks 124which in turn are pivoted by means of fulcrum pins 126 to the rearabutments 114.

Similarly positioned cranks 128 are likewise pivoted at 130 to theforward abutments 112 respectively and are slaved to the rearward cranks124 through pivoted linkages 132. At the points of their contact withthe underside of the support plate 58, the cranks 124, 128 are providedwith rollers to reduce frictional engagement, particularly when thesupporting plate 58 and the floor plate 42 thereon are moved between theforward and rearward positions thereof, as shown respectively in FlGS. land 5. At the lowermost position of the roll changing components(chain-outline 86, FIG. 1) the forward rolls of the cranks 124, 128 arealigned with the slideways 94 such that the support plate 58 first rollsalong the cranks 124, 128 and then engages the slideways 94 by virtue ofthe aforementioned slide blocks 90 affixed to the underside of thesupport plate 58.

Following on from the earlier operational description of theside-shifting plate 42, the operation of the remainder of theroll-changing components, including the elevational means, will now bedescribed. In the solid outline positions of the elevating means 110(FIG. 1) the longer stroke cylinders 116 have been fully extended toposition the cranks 124, 128 at their solid outline positioncorresponding to the intermediate or inactive, floor level position ofthe side-shifting floor plate 42. Whenever it is desired to align thefloor plate rails 38 or 40 with the upper mill rails 48 the smallerstroke cylinders 118 are likewise extended (while the longer strokecylinder 116 are maintained in their extended condition) to move therear cranks 124 to their chain outline positions 130 (the front crank128 are similarly moved) at which positions the rear rollers 132 thereofcontact the underside of. support plate 58 to move both the supportplate 58 and the floor plate 42 to the uppermost or chain outlineposition 84 thereof. On the other hand to permit withdrawal of the lowerbackup roll 54 both of the cylinders 116, 118 are fully retracted tomove the rear cranks 124 to their chain outline position 134 at whichpoint their front rollers 136 are engaged with the underside of thesupport plate 58 (as in the intermediate or solid outline positionthereof) and in addition are aligned with the slideways 94 as aforesaid.The front cranks 128 are moved to similar positions corresponding to thechain outline positions 130, 134 of the rear cranks 124 by means of thelinkages 132.

The divided nature of the elevating means including the cylinderarrangement 110 permits the lower backup roll assembly to be movedtherebetween. In consequence it is not necessary to withdraw theaforementioned elevating means with the remaining components of the rollchanging system 20. Upon operation of the traction means 106 suchremaining components, by virtue of their sliding connection 102-104 withthe drawbar 100, are moved to the rear or away from the mill stand 22along with the lower backup roll assembly 52. When the backup rollassembly has been fully withdrawn, the movable components of the rollchanging apparatus 20, including the floor plate 42 and its supportplate 58 are moved entirely beneath the fixed floor area 88 as shown inFIG. 5. The latter roll changing components are thus moved to a positionof minimal interference with other mill activities, including removaland replacement of the lower backup roll, and also are fully protectedby the overlying floor structure From the foregoing it will be seen thata novel and efficient side-shifting mill roll changing system has beendescribed herein. The descriptive and illustrative materials employedherein are utilized for purposes of exemplifying the invention and notin limitation thereof. Accordingly, numerous modifications of theinvention will occur to those skilled in the art without departing fromthe spirit and scope of the invention. Moreover, it is to be understoodthat certain features of the invention can be used to advantage withouta corresponding use of other features thereof.

I claim:

1. Mill roll changing apparatus for positioning transversely of arolling mill pass line and arranged for re ceiving and inserting millrolls relative to a juxtaposed mill stand, said apparatus comprising amovable floor section normally covering a roll changing pit adjacentsaid mill stand, a support structure for said floor section andpositionable within said pit, a number of rails on said floor section,driving mechanism for moving said floor section laterally of saidsupport structure in a direction generally parallel to said pass line sothat selected pairs of said rails can be laterally aligned with a pairof rails within said mill stand, and an elevating mechanism mountablewithin said pit and structured for elevating said floor section to afirst position above an existing floor surrounding said pit so that saidfloor section can be moved laterally thereof and to a second positionwhereat said floor section is flush with said existing floor and to athird position whereat said floor section is recessed within said pit.

2. The combination according to claim 1 wherein said floor section railsare machined into the surface thereof. t

3. The combination according to claim 1 wherein said driving mechanismis mounted on said support structure for movement therewith.

4. The combination according to claim 1 wherein said elevating mechanismincludes at least one pair of piston-cylinder arrangements mounted backto back.

5. The combination according to claim I wherein said pit is elongated ina direction transversely of said mill pass line and extends beneath saidexisting floor, and guideways are mounted in said pit and beneath saidexisting floor, said guideways being aligned with the lowermost positionof said floor section, and traction means are provided for drawing saidfloor section and its support along said guideways to a position beneathsaid existing floor and away from the open area of said pit.

6. The combination according to claim 5 wherein said pit is shaped toreceive a lower backup roll assembly from said mill stand and saidtraction means are coupled to said lower assembly for drawing saidassembly into said pit simultaneously with withdrawal of said 9. Thecombination according to claim 8 wherein said elevating means include apair of elevating mechanisms spaced laterally of one another and of thecentral area of said pit in order to accommodate passage of said drivingmechanism therebetween.

10. The combination according to claim 1 wherein said driving mechanismincludes rack and pinion means mounted on said floor section and supportstructure and extending generally parallel to said mill pass line.

1. Mill roll changing apparatus for positioning transversely of arolling mill pass line and arranged for receiving and inserting millrolls relative to a juxtaposed mill stand, said apparatus comprising amovable floor section normally covering a roll changing pit adjacentsaid mill stand, a support structure for said floor section andpositionable within said pit, a number of rails on said floor section,driving mechanism for moving said floor section laterally of saidsupport structure in a direction generally parallel to said pass line sothat selected pairs of said rails can be laterally aligned with a pairof rails within said mill stand, and an elevating mechanism mountablewithin said pit and structured for elevating said floor section to afirst position above an existing floor surrounding said pit so that saidfloor section can be moved laterally thereof and to a second positionwhereat said floor section is flush with said existing floor and to athird position whereat said floor section is recessed within said pit.2. The combination according to claim 1 wherein said floor section railsare machined into the surface thereof.
 3. The combination according toclaim 1 wherein said driving mechanism is mounted on said supportstructure for movement therewith.
 4. The combination according to claim1 wherein said elevating mechanism includes at least one pair ofpiston-cylinder arrangements mounted back to back.
 5. The combinationaccording to claim 1 wherein said pit is elongated in a directiontransversely of said mill pass line and extends beneath said existingfloor, and guideways are mounted in said pit and beneath said existingfloor, said guideways being aligned with the lowermost position of saidfloor section, and traction means are provided for drawing said floorsection and its support along said guideways to a position beneath saidexisting floor and away from the open area of said pit.
 6. Thecombination according to claim 5 wherein said pit is shaped to receive alower backup roll assembly from said mill stand and said traction meansare coupled to said lower assembly for drawing said assembly into saidpit simultaneously with withdrawal of said floor section and saidsupport to their position beneath said existing floor.
 7. Thecombination according to claim 5 wherein said support structure iscoupled to said traction means through a sliding pedestal and sleevearrangement so that said support structure and said floor section remaincoupled to said traction means irrespective of the elevation thereof. 8.The combination according to claim 5 wherein said driving mechanism ismounted on the underside of said support structure for movementtherewith.
 9. The combination according to claim 8 wherein saidelevating means include a pair of elevating mechanisms spaced laterallyof one another and of the central area of said pit in order toaccommodate passage of said driving mechanism therebetween.
 10. Thecombination according to claim 1 wherein said driving mechanism includesrack and pinion means mounted on said floor section and supportstructure and extending generally parallel to said mill pass line.